Gtk2::CellRenderer
- NAME
- DESCRIPTION
- HIERARCHY
- METHODS
- boolean = $cell->activate ($event, $widget, $path, $background_area, $cell_area, $flags)
- $cell->editing_canceled
- (width, height) = $cell->get_fixed_size
- $cell->set_fixed_size ($width, $height)
- $cell->render ($drawable, $widget, $background_area, $cell_area, $expose_area, $flags)
- (x_offset, y_offset, width, height) = $cell->get_size ($widget, $cell_area)
- celleditable or undef = $cell->start_editing ($event, $widget, $path, $background_area, $cell_area, $flags)
- $cell->stop_editing ($canceled)
- PROPERTIES
- SIGNALS
- ENUMS AND FLAGS
- DERIVING NEW CELL RENDERERS
- SEE ALSO
- COPYRIGHT
Gtk2::CellRenderer - An object that renders a single cell onto a Gtk2::Gdk::Drawable
The Gtk2::CellRenderer is the base class for objects which render cells
onto drawables. These objects are used primarily by the Gtk2::TreeView,
though they aren't tied to them in any specific way.
Typically, one cell renderer is used to draw many cells onto the screen.
Thus, the cell renderer doesn't keep state; instead, any state is set
immediately prior to use through the object property system. The cell
is measured with get_size, and then renderered with render.
Glib::Object
+----Glib::InitiallyUnowned
+----Gtk2::Object
+----Gtk2::CellRenderer
Since: gtk+ 2.4
Fetch the fixed size if $cell. Values of -1 mean "this dimension is not
fixed."
Set the renderer's size explicitly, independent of object properties. A value
of -1 means "don't use a fixed size for this dimension."
Since: gtk+ 2.6
- 'cell-background' (string : writable / private)
-
Cell background color as a string
- 'cell-background-gdk' (Gtk2::Gdk::Color : readable / writable / private)
-
Cell background color as a GdkColor
- 'cell-background-set' (boolean : readable / writable / private)
-
Whether this tag affects the cell background color
- 'height' (integer : readable / writable / private)
-
The fixed height
- 'is-expanded' (boolean : readable / writable / private)
-
Row is an expander row, and is expanded
- 'is-expander' (boolean : readable / writable / private)
-
Row has children
- 'mode' (Gtk2::CellRendererMode : readable / writable / private)
-
Editable mode of the CellRenderer
- 'sensitive' (boolean : readable / writable / private)
-
Display the cell sensitive
- 'visible' (boolean : readable / writable / private)
-
Display the cell
- 'width' (integer : readable / writable / private)
-
The fixed width
- 'xalign' (Glib::Float : readable / writable / private)
-
The x-align
- 'xpad' (Glib::UInt : readable / writable / private)
-
The xpad
- 'yalign' (Glib::Float : readable / writable / private)
-
The y-align
- 'ypad' (Glib::UInt : readable / writable / private)
-
The ypad
- editing-canceled (Gtk2::CellRenderer)
- editing-started (Gtk2::CellRenderer, Gtk2::CellEditable, string)
Gtk+ provides three cell renderers: Gtk2::CellRendererText,
Gtk2::CellRendererToggle, and Gtk2::CellRendererPixbuf.
You may derive a new renderer from any of these, or directly from
Gtk2::CellRenderer itself.
There are a number of rules that must be followed when writing a new
cell renderer. First and foremost, it's important that a certain set of
properties always yields a cell of the same size, barring a Gtk2::Style
change. The cell renderer also has a number of generic properties that
are expected to be honored by all children.
The new renderer must be a GObject, so you must follow the normal procedure
for creating a new Glib::Object (i.e., either Glib::Object::Subclass or
Glib::Type::register_object). The new subclass can customize the object's
behavior by providing new implementations of these four methods:
- (x_offset, y_offset, width, height) = GET_SIZE ($cell, $widget, $cell_area)
- o $cell (Gtk2::CellRenderer)
- o $widget (Gtk2::Widget) widget to which $cell is rendering
- o $cell_area (Gtk2::Gdk::Rectangle or undef) The area a cell will be allocated, or undef.
Return Values:
- - x_offset - x offset of cell relative to $cell_area
- - y_offset - y offset of cell relative to $cell_area
- - width - width needed to render cell
- - height - height needed to render cell
This is called to calculate the size of the cell for display, taking into
account the padding and alignment properties of the parent. This one will
be called very often. If you need to know your cell's data, then get it
from the appropriate object properties, which will be set accordingly before
this method is called.
- RENDER ($cell, $drawable, $widget, $background_area, $cell_area, $expose_area, $flags)
- o $cell (Gtk2::CellRenderer)
- o $drawable (Gtk2::Gdk::Drawable) window on which to draw
- o $widget (Gtk2::Widget) widget owning $drawable
- o $background_area (Gtk2::Gdk::Rectangle) entire cell area (including tree expanders and maybe padding on the sides)
- o $cell_area (Gtk2::Gdk::Rectangle) area normally rendered by a cell renderer
- o $expose_area (Gtk2::Gdk::Rectangle) area that actually needs updating
- o $flags (Gtk2::CellRendererState) flags that affect rendering
This is called to render the cell onto the screen. As with GET_SIZE, the
data for the cell comes from object properties. In general, you'll want to
make use of Gtk2::Style methods for drawing anything fancy.
The three passed-in rectangles are areas of $drawable. Most renderers draw
within $cell_area; the xalign, yalign, xpad, and ypad fields of the
cell renderer should be honored with respect to $cell_area.
$background_area includes the blank space around the cell, and also the
area containing the tree expander; so the $background_area rectangles for
all cells cover the entire $drawable. $expose_area is a clip
rectangle.
- boolean = ACTIVATE ($cell, $event, $widget, $path, $background_area, $cell_area, $flags)
- o $cell (Gtk2::CellRenderer)
- o $event (Gtk2::Gdk::Event)
- o $widget (Gtk2::Widget) widget that received the event
- o $path (string) widget-dependent string representation of the event location; e.g. for a Gtk2::TreeView, a string representation of a Gtk2::TreePath.
- o $background_area (Gtk2::Gdk::Rectangle) background area as passed to
RENDER.
- o $cell_area (Gtk2::Gdk::Rectangle) cell area as passed to
RENDER.
- o $flags (Gtk2::CellRendererState) render flags
This method is called when an event occurs on a cell. Implementing it is
not mandatory. The return value should be TRUE if the event was
consumed/handled.
- celleditable or undef = START_EDITING ($cell, $event, $widget, $path, $background_area, $cell_area, $flags)
- o $cell (Gtk2::CellRenderer)
- o $event (Gtk2::Gdk::Event)
- o $widget (Gtk2::Widget) widget that received the event
- o $path (string) widget-dependent string representation of the event location; e.g. for a Gtk2::TreeView, a string representation of a Gtk2::TreePath.
- o $background_area (Gtk2::Gdk::Rectangle) background area as passed to
RENDER.
- o $cell_area (Gtk2::Gdk::Rectangle) cell area as passed to
RENDER.
- o $flags (Gtk2::CellRendererState) render flags
For cells that are editable, this is called to put the cell into editing
mode. If the return value is an object is a Gtk2::CellEditable, that
widget will be used to edit the value; the calling code takes care of
sizing, placing, and showing the editable, you just need to return it.
If the return value is undef, the editing is aborted.
Note: for backward compatibility, the bizarre and non-standard scheme used
for this in 1.02x is still supported, but is deprecated and should not be
used in new code, and since i don't want people to use it any more i will
not document it here.
Gtk2, Glib::Object, Glib::InitiallyUnowned, Gtk2::Object
Copyright (C) 2003-2008 by the gtk2-perl team.
This software is licensed under the LGPL. See Gtk2 for a full notice.
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